Hastening or forward; hence, tending to further or promote a proposed object; fit or proper under the circumstances; conducive to self-interest; desirable; advisable; advantageous; -- sometimes contradistinguished from right.

It is expedient for you that I go away.
John xvi. 7.

Nothing but the right can ever be expedient, since that can never be true expediency which would sacrifice a greater good to a less.
Whately.